Women Treated for Breast Cancer Seem To Age Faster
Women who received breast cancer treatment, particularly radiation therapy, were older, biologically, than women who were never diagnosed with breast cancer, according to a study.
The research was published online on July 19, 2023, by the Journal of the National Cancer Institute. Read “Changes in methylation-based aging in women who do and do not develop breast cancer.”
Biological age versus chronological age
Your chronological age is the number of years you’ve been alive. Your biological age is how old your body seems, based on a number of factors, including how your chromosomes have changed over time.
In this study, the researchers used three tests measuring DNA methylation to calculate biological age.
DNA stands for deoxyribonucleic acid, a substance that is the main component of chromosomes. DNA methylation is a chemical change to DNA that is part of the normal aging process. DNA methylation that happens in abnormal patterns — meaning some DNA that should methylate doesn’t and DNA that should not methylate does — has been linked to cancer. Scientists think that DNA methylation and biological age may be affected by exposure to things in the environment, such as sunlight, automobile exhaust, alcohol, and chemicals in food, plastics, and water.
About the study
This analysis included information from 417 women who are part of the Sister Study, an on-going study monitoring more than 50,000 sisters of women diagnosed with breast cancer to look for environmental and genetic links to the disease. When the women joined the Sister Study between 2003 and 2009, they had never been diagnosed with breast cancer and provided a blood sample. Another blood sample was collected five to 10 years later.
The average time between blood draws for the women in the study was about 7.5 years.
Among the 417 women whose information was analyzed:
190 women were diagnosed and treated for breast cancer between the first and second blood draw
227 women remained cancer-free
Among the 190 women diagnosed with breast cancer:
55 were diagnosed with DCIS
91 were diagnosed with stage I breast cancer
38 were diagnosed with stage II breast cancer
6 were diagnosed with stage III breast cancer
all the women had surgery to remove the cancer
67 received chemotherapy
121 received radiation
130 took hormonal therapy
The researchers used the three DNA methylation tests on the blood samples to measure the women’s biological aging between the two blood draws.
Women who were diagnosed with breast cancer had faster biological aging as measured by all three DNA methylation tests than women who were cancer-free. There were no differences in biological aging based on race.
The researchers also checked to see if faster biological aging was linked to any of the four treatments the women received.
They found that surgery had no effect on biological aging, but chemotherapy, hormonal therapy, and radiation therapy all contributed to faster biological aging. Biological age increased the most in women who received radiation therapy.
“Radiation is a valuable treatment option for breast cancer, and we don’t yet know why it was most strongly associated with biological age,” Dale Sandler, PhD, chief of the National Institute of Environmental Health Sciences Epidemiology Branch and paper co-author said in a statement. “This finding supports efforts to minimize radiation exposures when possible and to find ways to mitigate adverse health effects among the approximately 4 million breast cancer survivors living in the United States.”
The researchers emphasized that women should not avoid radiation therapy based on the results. Current breast cancer treatment regimens that include radiation therapy are very effective in reducing the risk of recurrence (the cancer coming back).
What this means for you
Although the results of this study are concerning, other studies suggest there are some steps you can take to slow DNA methylation.
Certain nutrients, including folate, choline, vitamin B12, and vitamin B6, play a role in DNA methylation. So some researchers think that eating more foods containing these nutrients can help keep the DNA methylation process normal.
Folate is a B vitamin found in dark green leafy vegetables, such as spinach or greens, as well as meat, seafood, dairy products, and other foods. Spinach, liver, asparagus, and brussels sprouts are some foods with the highest levels of folate.
Choline is an essential nutrient found in meat, poultry, fish, dairy products, eggs, and cruciferous vegetables, such as broccoli. Choline is a source of the methyl groups that are needed for DNA methylation.
Vitamin B12 is naturally found in animal products, including fish, meat, poultry, eggs, milk, and milk products. Beef liver and clams have some of the highest levels of vitamin B12.
Vitamin B6 is found in a variety of foods, including fish, beef liver and other organ meats, potatoes and other starchy vegetables, and non-citrus fruit. Chickpeas (garbanzo beans), tuna, and salmon have some of the highest levels of vitamin B6.
In mice, a restricted calorie diet has been shown to slow DNA methylation. Some scientists think that intermittent fasting – eating at specific times during the day – may do the same thing in people.
Getting regular exercise and quality sleep can also help slow DNA methylation.
— Last updated on November 14, 2023 at 2:07 PM